import java.util.*;

class Point {
    int x, y;

    Point(int x, int y) {
        this.x = x;
        this.y = y;
    }
}

class Node extends Point {
    int dist;

    Node(int dist, int x, int y) {
        super(x, y);
        this.dist = dist;
    }
}

public class _16236 {
    static boolean inField(int x, int y, int N) {
        return (0<=x && x<N) && (0<=y && y<N);
    }
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();

        int[][] field = new int[N][N];
        Point shark = new Point(0, 0);

        for(int i=0; i<N; i++) {
            for(int j=0; j<N; j++) {
                field[i][j] = sc.nextInt();

                if(field[i][j]==9) {
                    shark.x = j;
                    shark.y = i;
                    field[i][j] = 0;
                }    
            }
        }

        sc.close();

        int sharkSize = 2;
        int eatCount = 0;
        int moveTime = 0;

        PriorityQueue<Node> pq = new PriorityQueue<>((a, b) -> {
            if(a.dist == b.dist) {
                if(a.y == b.y) return a.x - b.x;
                return a.y - b.y;
            }
            return a.dist - b.dist;
        });

        int[] dx = {0,-1,1,0};
        int[] dy = {-1,0,0,1};

        while(true) {
            boolean[][] visited = new boolean[N][N];
            boolean eatFish = false;
            pq.clear();
            visited[shark.y][shark.x] = true;
            pq.add(new Node(0, shark.x, shark.y));

            while(!pq.isEmpty()) {
                Node now = pq.poll();

                if(field[now.y][now.x] != 0 && field[now.y][now.x] < sharkSize) {
                    field[now.y][now.x] = 0;
                    shark.x = now.x;
                    shark.y = now.y;
                    eatCount++;
                    moveTime += now.dist;
                    eatFish = true;

                    if(sharkSize == eatCount) {
                        eatCount = 0;
                        sharkSize++;
                    }

                    break;
                }

                for(int i=0; i<4; i++) {
                    int nx = now.x + dx[i];
                    int ny = now.y + dy[i];

                    if(inField(nx, ny, N) && !visited[ny][nx] && field[ny][nx] <= sharkSize) {
                        pq.add(new Node(now.dist + 1, nx, ny));
                        visited[ny][nx] = true;
                    }
                }
            }

            if(!eatFish) break;
        }

        System.out.println(moveTime);
    }
}